Twisted stem tufted brush



, Feb. 21, 1961 2,972,157

. I law I! r ed May 8, 1957 INVENTOR. ZUBEN O. PETERSON BY a: z '0 4 A ORNL'YS. I

e 2,972,151 Ice Patented Feb. 21, 1961 TWISTED STEM TUFI'ED BRUSH Ruben 0. Peterson, University Heights, Ohio, assignor to The Osborn Manufacturing Company, Cleveland, Ohio, a corporation of Ohio Filed May 8, 1957, Ser. No. 657,927

Claims. (Cl. 15-206) This invention relates as indicated to a twisted stem brush, and more particularly to one in which a plurality of individual separate tufts of brush bristle material are gripped and held by a twisted stem with such tufts projecting in different directions radially of the stem.

In my prior application Serial No. 553,317, filed December 15, 1955, now Patent No. 2,895,155, entitled Wire Stem Brush, I disclose and claim a twisted stem brush having a fiat tuft or layer of brush bristle material gripped and held between opposed stem wire lengths, such stem wire being of a particular conformation enhancing the grip of the same on the brush bristles as well as providing certain other advantages. In my prior copending application Serial No. 640,652, filed February 18, 1957, entitled Brush Element and Belt Brush Construction, I disclose and claim a novel brush element com prising a plurality of individual tufts gripped and held by a wire stem member and projecting in the same direction, these brush elements being particularly suitable for mounting on endless belts or other like supporting means. The present invention incorporates certain of the features of each of these prior inventions in a new manner to provide a different type of brush. 7

It is an object of my invention to provide a twisted stem tufted brush and method of manufacturing the same especially adapted for continuous automatic manufacture.

Another object is to provide such new brush and meth- 0d of manufacture wherein the individual separate tufts may radiate in any desired directions from the central stem.

Still another object is to provide such brush in which each tuft may comprise a relatively long flat layer of brush material.

A further object is to provide a brush of the type indicated adapted to be mounted for rotation about the longitudinal axis of the stem.

Other objects of the invention will appear as the description proceeds.

To the accomplishment of the foregoing and related ends, said invention then comprises the features hereinafter fully described and particularly pointed out in the claims, the following description and the annexed drawing setting forth in detail certain illustrative embodiments of the invention, these being indicative, however, of but a few of the various ways in which the principle of the invention may be employed.

In said annexed drawing:

Fig. 1 shows a novel tufted brush element suitable for use for some purposes but particularly adapted for further modification to form the brush of Fig. 3;

Fig. 2 is a transverse section taken on the line 2-2 on Fig. 1;

Fig. 3 is a transverse section similar to Fig. 2 but wherein the central stem members have been further twisted intermediate successive tufts longitudinally thereof so that the ends of such tufts define two helices, each 7, "tuft being somewhat circumferentially offset from the next adjacent tufts;

Fig. 4 is a transverse section similar to Fig. 2 on an enlarged scale showing a preferred form of stem wire cross-section;

Fig. 5 is a view resembling Fig. 4 but including pro vision of a bonding and cushioning agent;

Fig. 6 resembles Fig. 5 but illustrates a somewhat different stem wire cross-section and another form of cushioning agent; and

Fig. 7 is a view similar-to Fig. 6 but showing each stem wire element entirely enclosed by such cushioning agent.

Referring now more particularly to Figs. 1 and 2 of the drawing, the embodiment of my invention there illustrated comprises two generally half-round stem wires 1 and 2 twisted together with their generally flat (or slightly concave) faces opposed and clamping therebetween generally fiat layers of brush bristle material 3, such individual flat layers or bundles of brush material forming pairs of oppositely extending tufts 4 and 5. It will be seen that in a sense each bristle bundle is secured in a manner generally comparable to those of Peterson and Charvat Patent 2,465,396. Of course, a variety of different types of brush material may be thus secured, including bristles such as crimped wire of steel and nonferrous metals, synthetic plastic bristles, and also composite strands such as plastic coated wire, crimped or straight, and plastic coated glass filaments, and strands of abrasive bearing longitudinally rolled film such as are taught in Patents Nos. 2,682,734 and 2,609,642. Also, various types of abrasive fabrics and boiling material may be utilized instead of bristle materials.

It will be noted that the wires 1 and 2 are twisted together intermediate successive tufts, thereby both spacing and clamping the same. directly engaging and gripping the brush material will ordinarily be substantially straight although they may also be slightly twisted if desired.

As shown in Fig. 4, such wire stem members may be of general half-round cross-section having substantially flat faces 6 or edge portions 7 and 8 protruding somewhat beyond such face and thus forming long narrow ridges longitudinally of the wire. Such edge or ridge portions 7 and 8 are rounded to avoid the formation of any sharply definededge which might tend to cut the bristles or cause localized concentrations of stress which would result in long fracture of such bristles. As will be readily apparent, the brush bristle material 3 is gripped principally between the opposed rounded edge portions 7, 7 and 8, 8 with the central region of the brush material being permitted to bulge somewhat Within the larger space afforded between the opposed faces 6. The brush material is accordingly firmly held both against lengthwise withdrawal from between the stem members and also against swiveling action.

The modification illustrated in Fig. 5 resembles that of Fig. 4 with a further provision of a layer of plastic material 9 against each of the flat surfaces 6, more or less filling the recesses between the protruding edge portions 7 and 8. The brush bristles may still bulge somewhat Within the cavity between the opposed faces 6 but are embedded in and gripped by the plastic material. Such plastic material will desirably have strong adhesive qualities, the epoxy resin compositions being particularly suitable, and they will be applied to the faces 6 of the stem members prior to clamping the same about the layer of brush material. Preferred adhesive bonding agents are epoxy resin plasticized with polyethylene glycol, and epoxy resin plasticized with liquid Thiokol polymer.

These materials are elfective in bonding and cushioning a wide variety of brush bristle materials.

In Fig. 6, another modification is illustrated where the opposed stem members 10 and 11 are of generally half-round cross-section with longitudinally concave op The opposed wire portions e w a,972,1s7

posed faces 12 generally comparable to the recess faces 6 of Figs. 4 and 5 but affording somewhat more gently rounded contours. The stem members may be of annealed, half-round cotter wire having a Rockwell hardness of 1330-50, for example. Aribbon of elastoeric material13 is applied'to each such :groove or recessed surface 12, such ribbon being wide enough to extend between the most closely opposed side edge portions of stem members and 11. The :brush material gripped therebetween is accordingly secured in the same general manner as that in Fig. 5 but is also gripped and cushioned by the elastomeric material where it emerges from between the stem members, reducing vibratory concentrations of stress in use .and .achievinglonger brush life. The elastic material '13 of 'Fig. 6, which may for example be'rubber or Neoprene tape, will ordinarily be bonded tothe wire stem members by an appropriate adhesive such as rubber lcement.

The Fig. 7 embodiment is similar to that of Fig. 6 except that the wire stem members 10 and 11 are completely coated with elastomeric sheaths'ld which may be extruded thereon or applied by means of a latex :dip. Such elastomeric material may be compositions of natural rubber, Neoprene, butadiene-styrene copolymer, butadi- -ene-acrylonitrile copolymer, vinyl-acetate copolymer, styrene copolymer, vinyl chloride-vinyl acetate copolymer,

and vinylidene chloride-vinyl chloride copolymer, or other well-known resiliently deformable material, as may be desired. Plastics such as nylon may also be. preferred materials for this purpose. These same materials may be deposited in the Fig. 5 grooves also.

When steel brush bristle material is employed, it may often be advantageous to employ steel wire having a relativelyhigh Knoop'hardness (at least 600 Knoop), Hadfield steel being a suitable example. When such bristle -materials are employed, it is particularly. desirable that they be gripped and held by cushioning materials such as those of Figs. 6 and 7. The individual bristle wires may also be coated with a thin vibration damping plastic coating such as nylon bonded thereto by means of an epoxy resin cement.

Referring now more especially to Fig. 3, it will be understood that the double tufted brush strip of Fig. 1

may be further twisted between each successivepair of tufts to offset such successive tufts'circumferentially of the central stem. in Fig. 3, it will be understood that tufts 44C represent such successive tufts originally aligned on one side of the stem wire and that tufts 5-5C .represent the corresponding diametrically opposed tufts hers may be of relatively sturdy cross-section and twisted togetler in a very-precise manner to provide a central stem or support of little or noeccentricity.

The wire stem members or retainingelements l and 2 are placed on opposite sides of a continuous layer or band of the selected brushmaterial, which band is'confined as to width to which it might spread in. theregion of contact with suchstem members, 'andheavyprcssure is applied thereto to compact such'layer therebetween.

At a suitable time in the process of manufacture of the brush element, such layer or band of brush material is severed at the desired distance from the stem wires to produce a tuft of proper length, and the'stem wires are twisted preferably 360 or some -multiple thereof, the oppositely projecting tufts rotating during such operation. The pressure compacted tuft: is thus tightly confined. At a suitable time in the process of manufacture,

the brush material layer-orv bandend which has been 75' stem or base.

severed in forming a previous tuft is advanced and positioned between separated wires 1 and 2 adjacent the twisted portion of the stem Wires and the previously positioned and clamped brush material tuft secured thereby, and the layer is again confined and subjected to heavy pressure while held between the stem wires pressed thereagainst, and severed to the desired tuft length prior to twisting the wires with rotation of all previously severed tufts together. Repetition of these operations may produce an elongated brush element comprising an alignment of'spaced parallel tufts secured to a twisted wire Rather-than thus twisting the wires together, they may be otherwise joined as by spot welding intermediate the tufts.

When the brush is to be formed into the Fig. 3 embodiment of my invention, I will ordinarily first form the Fig. 1 embodiment as above described and then continuously progressively twist a predetermined length thereof 360 from end to end with consequential circumferential offset of successive tufts. Of course, the degree of twist may be varied as desired and such furthertwisting may be confined to the already twisted regions intermediate the successive tufts, thereby maintaining the individual tufts more in a plane including the stem. Alternatively, the initial twisting operations in the formation of the brush element may be performed to achieve such circumferential offset of the tufts instead of forming the Fig. l fiat strip as an intermediate stage.

When compacting the fiat layers of bristle material *3 between the wire stem members preparatory to securing such stem members together as by twist-fi it will be desirable to apply very heavy pressure on the order of several thousand pounds per square inch (e.g. 10,000-- 20,000 pounds per square inch or more in the case of crimped wire brush material). The wire stem members will ordinarily be gripped and held stationary while another par of die members grip the stem portions embracing the layers of brush material to rotate the same 2,303,386 with the pairs of tufts extending outwardly from the channel side by side.

Other modes .of applying the principle of the invention may be employemchange being made as regards the details described, provided the features stated in any of the following claims or the equivalent of such be employed.

I therefore particularly point out and distinctly claim as my invention:

1. As a new article of manufacture, a brush element comprising two wires secured together at longitudinally spaced intervals to form a stem, and brush material interposed at intervals transversely between said wires to form a series of spaced pairs of fiat oppositely extending tufts, said stern wires being thus secured together only in the regions intermediate said pairs of tufts to clamp and space the latter, wherein the portions of. said stern wires clamping said brush material are straight, successive pairs of oppositely extending flat tufts are thus clamped by said wires, and said stem wires are twisted in the intervening regions only circumferentiallyto offset successive fiat tufts in helical fashion.

2. The method of manufacturing a brush element which comprises twisting together two generally halfround wire stem members with their convex surfaces outwardly disposed, placing a fiat layer of brush bristle material transversely between such members toform a pair of oppositely extending tufts, compacting such layer forcibly between such stem members, twisting such stem .members together closely beyond such layer to secure the same together, similarly placing another flat. layer of brush bristle material between such stem members immediately beyond the last twisted portion, compacting such latter layer forcibly between such stem members, and twisting such members together closely beyond such latter layer to secure the same together while permitting such previous layer and twisted stem portions to revolve with such latter twisting operation, such latter twisting operation being concluded with the tufts of such latter flat layer lying in the same plane as the tufts of the first mentioned fiat layer but spaced therefrom by the intermediate twisted portion of such stem.

3. The method of claim 2, including the steps of further twisting such stem members intermediate said successive layers only to circumferentially otfset successive tufts.

' 4. The method of claim 2, including the step of further twisting such stem members throughout their layer clamping length to circumferentially offset such successive tufts in general helical manner.

5. As a new article of manufacture, a brush element comprising two wires secured together at longitudinally spaced intervals to form a stem, and brush material interposed at spaced intervals transversely between said wires to form a series of pairs of flat oppositely extending tufts, said stem wires being thus secured together only in the regions intermediate said pairs of tufts to clamp and space the latter, and the faces of said stem wires engaging said brush material being of substantial width better to grip said material and maintain said tufts flat, wherein numerous successive layers of brush material are thus arranged and secured in longitudinally spaced regions along said stem, and said stem is twisted circumferentially to offset successive pairs of tufts, 7

References Cited in the file of this patent UNITED STATES PATENTS 1,034,576 Braun Aug. 6, 1912 1,206,273 Veeck et al. Nov. 28, 1916 2,465,396 Peterson et a1 Mar. 29, 1949 2,580,378 Peterson et al. Dec. 25, 1951 2,895,155 Peterson July 21, 1959 FOREIGN PATENTS Y 139 Great Britain Jan. 15, 1866 13,324 Germany Apr. 28, 1881 13,962 Germany June 14, 1881 195,184 Great Britain Mar. 29, 1923 409,462 Great Britain May 3, 1934 615,796 France Ian. 15, 1927 

